Pulp strainer



M. LAMORT PULP STRAINER Jan. 30; 1934.

Filed June 4, 1932 '4 Sheets-Sheet l Jan. 30, 1934. LAMORT I 1,945,492

PULP STRAINER Filed June 4, 1932 4 Sheets-Sheet 2' Jan. 30; 1934. LAMORT 1,945,492

PULP STRAINER 1 Filed June 4,1952 4 Sheets-Sheet 3 4 Shgts-Sheet 4 M. LAMORT PULP STRAINEB Jan. 30, 1934.

Patented Jan. 30, 1934 1,945,452 PULP STRAINER Marcel Lamort, Vitry-le-Francois, France, as-

signor to 'Etablissements E. & M. Lamort Fils, Yitry-le-Francois, France Application June 4, 1932, Serial No. 615,451, and l in France-lune 8, 1931 6 Claims. (01. 92-35) The present invention relates to purifying devices for paper pulp and the like. Such apparatus comprise perforated members which are slotted, as a rule, by the milling process, and are subject to a very rapid shaking by which the pulp will be strained and freed from its'impurities. Such apparatus thus resemble the-shaking sifters, and have nothing in common with filtering apparatus. Y

In the known devices of this class, the slotted portion has the form of a drum which rotates in a tank or vat. In some apparatus, the tank is fixed and the drum rotates at a slow rate in the said tank, while at the same time it is subjected to a rapid shaking, and thus the pulp is purified as a rule by circulating from the interior to the exterior of the drum. In other apparatus, the drum is not subject to shaking, and the pulp proceeds from the exterior to the interior of the drum under the action of shocks which are given to the tank itself or to blades or paddles contained therein. With the apparatus of the first-mentioned type, the level of the pulp is situated below the axis of the drum, and the latter has but a small efiective surface. On the other hand, the maximum eifect ofthe shocks is distributed over a small surface. In the other apparatus, the effective surface is also small, and for apart of the drum, the liquid moves in a direction parallel with the perforated surface, and this part affords but a small output.

In the apparatus constructed in conformity to the invention, the purifying drum consists of flat straining members which are mounted in starshape about a central shaft, thus affording an angular or corrugated surface at the periphery. This arrangement assures a large effective surface, andthe operation is uniform at all points of this surface. The apparatus has a very strong construction, thus avoiding all dangerous distortion. On the other hand, for a given effective surface, a minimum size, weight and cost are obtained. The drum is preferably made up of strainer plates of small size which are mounted in star-shape between two. end-plates to which they are removablysecured and this facilitates the construction and assembling.

The pulp is purified by rotating the drum on its axis by a jerking movement. It may be given an alternate rotary motion at a high rate, the

amplitude of the motion being greater in one direction than in the other, and thus the strainer plates are displaced by Jerks which are substantially perpendicular to-their surface, and they come into action according as the drum rotates.

Washing devices can be employed to clean the said plates when out of the tank.

Suitable. arrangement for obtaining the alternating motion of the drum comprises a belt which is held stationary at acertain part and which is mounted on a pulley keyed to the drum shaft. By means of rollers or the like, the strands of the belt are given alternate motion on either side of the mean position which is displaced from the common center line of the pulley and the belt-. holding device. Thus the pulley and'the drum are given an alternate movement of rotation, while 1 at the same time they advance slowly by jerks. An endless belt can be employed for the purpose, and it is mounted on a roller which is'held in place in order to constitute a fixed point.

In another arrangement, the drum shaftis driven by a motor by which it isgiven a continuous rotation by means of gearing, which latter is mounted on a frame adapted for arapid oscillation about the axis of the drum. In this manner the drum will oscillate on its axis at a high rate, while at the same time rotating at a very slow speed.

The accompanying drawings relate to an em bodiment of the inventio'nas disclosed in the following description.

Figure 1 is an elevational view, in section, of a form of construction of the apparatus.

Figure 2 is a section of the drum on a larger scale, on the line 11-11 of Figure 1.

Figure 3 is a detail view relating to the means for securing the perforated plates to the endtive shafts 3--4. Between the said plates are' located a certain number of slotted plates which i are mounted in star-shape, as represented in Figures 2 and 3, said plates are supported, according to generatrices of the drum, in V shaped troughs 6-7, in which they are held against rubber packing members 8-9; which assure a tight joint. vAt the periphery, said troughs are secured by brackets 10, and at the part next the center,

by a ring. 11. The plates 5 are inserted into grooves in the end-plates 1-2.

The drum thus formed has a more economical construction, and can be more readily assembled, than in the known devices. In fact, the manufacture of a certain number of perforated plates 5 of a relatively small size can be more readily effected than in the case of a single cylindrical sheet-metal piece, as usually employed. Furthermore, the device has a greater strength. against bending, this being an important feature by reason of the heavy strains occasioned by the severe shocksto which such apparatus are subjected. On the other hand, for an equal effective surface, the said apparatus has a much smaller size. Obviously, the periphery of the drum might be given acorrugated shape.

-In the shafts 3-4, and in the drum,- is mounted a stationary tube 12, divided into two parts by a partition 13. The paper pulp to be purified enters through a tube 14 and circulates in-the- .5 drum through orifices 15 formed in the tube 12.

The perforated plates 5 are cleared of waste matter by water streams supplied by the washing" exterior of the drum, but it 'is evident that it might circulate in' the contrary direction without departing from. the spirit of the invention.

The shafts 3 and 4 are mounted in suitable bearings, not shown, and are driven by pulleys 20, each of which is actuated by a like mechanism, of which only one will be described as follows.

ona roller 22 which is' heldin the fixed position by suitable means, not shown. A frame 23 (Figure 4) -is pivotally mounted on the axle of. the

stationary roller 22, and carries two small rollers 24-25, between which the belt ismovable. The said frame has an eccentric 28 whose shaft is operated by a motor, not shown, in continuous rotation.

The rollers 24-25 can be. moved upon the frame 23by adjusting screws 33 -34, and said rollers are mounted in, such" manner that in the mean position of, the frame, that is, when it is at an equal distance from its extreme pivoting positions, as shown innthe figure, the rollers will not be equally spaced from the center-line common to the two pulleys 20-22. In this event, when the shaft 29 rotates, the pulley 20 will rotate on its axis by slow degrees in the direction of the arrow 30. The rate of rotation in the direction of the arrow can be varied by changing the position of the movable rollers 24-25, and this rate ofrotation can be further modified by releasing the'roller 22 and rotating it at slow speed.

In the driving mechanism shown in Figure 5,

a worm-wheel 35 is mounted on the drum shaft 36. A frame 37 is pivotally mounted on the said fshaft, and it carries a worm 38 cooperating with said worm-wheel and'rotatable by a motor 39, by means of two cardan joints 4647 and a speedreducer 40 which is mounted on a bracket 41 secured to the frame 37. The assembly of the frame and reducer will thus, pivot about the shaft 36. The -motor.39 drives. the shaft 36 by the aforesaid gear, at a-speed of about one revolution per minute, in'the direction of the arrow 42.

The frame 3'1 carries a .lower appendage 43 ending in a rectangularguide 44 in which is movfrom about 2 to able an eccentric 45 rotatable at about 600 revolutions per minute. -,The eccentricity may vary 12 m n" and thus the frame 37 will make about600 oscillations per minute; whose amplitude is between 2 and 12 at the lower oscillate ata small amplitude and at-a relatively high rate, while at the same .time rotating at slow speed in the direction of the arrow 42. 'A mechanism of this construction is -mounted at each end of the drunr shaft 36. Having now particularly described and ascere'ndless belt 21 is mounted on a pulley 20 and the shaft 30 willtained the nature of my invention and in what manner the same is to be performed, I declare that what I claim is:

1. A purifying apparatus for paper paste, characterized by thefact that a plurality of straining surfaces are situatedobliquely or perpendicularly with reference to a main. surface, and that the shaking movements take place alternately, or by jerks, in a direction parallel with the said main surface.

2. A straining apparatus for paper pulp characterized by having a purifying drum provided with a peripheral straining surface of practically s'tar shape and further characterized by means for rotating said drum onits axis with anintermittent jerking movement, I

3. A straining apparatus for paper pulp characterized by having a purifying drumprovided with a peripheral straining surface of practically star shape and further characterized by means for rotating said drum in alternate directions at high frequency of change with the amplitudes of movement in one direction exceeding the amplitudes of movements inthe other direction whereby the drum will slowly rotate in the first direction with a jerking movement. I

4. 'A straining apparatusfor paper pulp characterized by having a purifying drum provided with a peripheral straining surface of practicallystar shape and further characterized by means for rotating saiddrum in alternate direc-y 5.- A straining apparatus for paper pulp char- 1 acterized by having a purifying drum provided with a peripheral straining surface of practically star shape and further characterized by means for rotating said drum in alternate directions at high frequency of change with the amplitudes of movement in one direction exceeding the amplitudes of movements-in the other direction whereby the drum will slowly rotate in the first direction with, a Jerking movement, the means for rotating the drum including a drum shaft, a pulley on said shaft, a' second pulleyspaced from the first pulley, a belt trained over. saidpulleys,

and a belt oscillating device engaging the parts of the belts between the pulleys and arranged to oscillate on either side of 'a mean position displaced. laterally of theline passing through the axes of said pulleys. Y

6. A straining apparatus for paper pulp characterized by having a purifying drum provided with a peripheral straining surface of practically star shape and further characterized by means for rotating said drum in alternate directions at high frequency of change with the amplitudes of movement in one direction exceeding the amplitudes of movements in the other direction whereby the drum will slowly rotate in the first direc-'- tion with a jerking movement, the means for rototing the drum including a motor,gearing:con-

necting the motor and drum, a frame supporting said gearing, and means for impartingrapid oscillatory motionto said frame.

- j MARCEL-LAMORT. 

